Penny Sorting Aluminum Channel - weight discriminate trap door.
Penny Sorting Aluminum Channel - weight discriminate trap door.
(OP)
I want to build a trap door about an inch long in a 1/2 wide aluminum channel down which pennies will slide. I want new pennies (weighing about 2.5 g) to continue, but old pennies (weighing 3+ g) to drop thru the hinged piece.
Can I use opposing compression and torsion springs to optain such fine control?
Any other top of the head ideas welcome.
Can I use opposing compression and torsion springs to optain such fine control?
Any other top of the head ideas welcome.





RE: Penny Sorting Aluminum Channel - weight discriminate trap door.
RE: Penny Sorting Aluminum Channel - weight discriminate trap door.
Glad I could answer your question.
RE: Penny Sorting Aluminum Channel - weight discriminate trap door.
The hinge pin should be parallel to the direction of the penny travel. If you do it perpendicular, the trailing pennies will fall like lemmings over a cliff.
The hinge "counterweight" can come from an actual weight or from the hinge material extending past the hinge to counteract the 2.5g pennies but not the 3.0g pennies.
Good luck.
RE: Penny Sorting Aluminum Channel - weight discriminate trap door.
RE: Penny Sorting Aluminum Channel - weight discriminate trap door.
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
RE: Penny Sorting Aluminum Channel - weight discriminate trap door.
Could not find tilting hinge of appropriate design, but can readily fabricate from wood, the bracket to hold a likewise fabricated calibrated teeter-tottor.
RE: Penny Sorting Aluminum Channel - weight discriminate trap door.
we made a sloping chute where the coins would roll down and strike an anvil, as the coin bounced, a microphone would pick up the ring tone. Depending on the tone a solenoid would activate, or not, deflecting the coin into one of two bins. one for the silver and one for the clad.
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor